Why Nibbana is classified as Nama in Abhidhamma?
The Ultimate Realities
The Abhidhamma deals with realities existing in an ultimate sense, called in Pali paramattha dhammaa. There are four such realities:
1. Citta, mind or consciousness, defined as that which knows or experiences an object. Citta occurs as distinct momentary states of consciousness.
2. Cetasikas, the mental factors that arise and occur along with the cittas.
3. Ruupa, physical phenomena, or material form.
Citta, the cetasikas, and ruupa are conditioned realities. They arise because of conditions and disappear when their conditions cease to sustain them. Therefore they are impermanent. Nibbaana is an unconditioned reality. It does not arise and therefore does not fall away. These four realities can be experienced regardless of what name we give them. Any other thing — be it within ourselves or without, past, present, or future, coarse or subtle, low or lofty, far or near — is a concept and not an ultimate reality.
Citta, cetasikas, and nibbaana are also called naama
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